The present invention relates to a system for controlling the power supplied from a power source to a load, or more in particular to a power supply control system capable of supplying electric power from a power source to a plurality of desired loads of different specifications or from a multiplicity of types of power sources to a plurality of loads having a variety of different specifications respectively.
In a high-power supply control system, the present invention preferably relates to a configuration and a method of controlling and operating a power supply system suitable for supplying electric power from a great variety of power sources to indoor services including various loads.
In a low-power supply control system, on the other hand, the present invention preferably relates to a system comprising a socket (convenience outlet) having a function of power conversion for connecting a power line to a plug connected to a desired load of a power specification different from that of the power line, and the plug having the function of the load power specification information.
A conventional power supply system for distributing large power to a plurality of loads, as described in "Mitsubishi Electrical Techniques", Vol. 60, No. 5, pp. 25-31 1986, supplies power from a commercial AC system to a load through a transformer. As a result, each load is required to have power conversion means to convert power into a form necessary for the particular load. Also, the conventional power supply system comprises two power transmission systems for normal and emergency services. Only the normal transmission system is used under normal conditions, while the emergency transmission system is operated only in case of emergency. The resulting lack of flexibility in the form of power supply makes it necessary to provide another power supply for preventing a power failure, thus posing a roadblock to reduction in the size of such a load system.
The failure to consider the flexibility of the form in which power is supplied to a load in the prior art prevents a load system from decreasing in size.
On the other hand, office automation (OA) equipments including home electric appliances and personal computers which receive relatively small power from a commercial AC power line have a respective power receiving cord with a plug making up their power input terminal, which is connected to a socket (convenience outlet) leading to the commercial power line. A socket in general use includes, as shown in FIG. 49, an input terminal connected to a commercial power line, and an output terminal to be connected to a load side plug 54, and a conductor for connecting the input and output terminals. The output terminal is replaceably constructed to facilitate the connection with or separation from the plug electrode 57. Also, the connecting portion of the commercial power line and the input terminal of the socket and the connecting portion of the output terminal and the plug electrode, are covered with an insulating material to prevent their complete exposure.
According to the above structure, the output voltage of the socket is equal to the commercial AC voltage applied thereto. On the load side, on the other hand, there is provided in many cases a switching power supply 84 for converting a commercial AC voltage received from the socket into a power level (DC 5 V, 12 V, etc.) required for driving the internal circuit of the load.
In the case of a load having a battery as a power supply, in order to make reception possible from a commercial power supply, an AC-DC converter 84 is often used. The converter 84 is inserted between a socket and a load side plug 54 as shown in FIG. 50 to convert a commercial AC voltage of 100 V into a DC voltages of 3 V or 1.5 V. The converter 84 is configured of a transformer 66, a rectifier 63 and smoothing means 82 as shown in FIG. 50. The taps of the transformer may be switchable by operating a tap switching means 83 provided on the surface of the converter body 84 to select an output voltage of 3 V or 1.5 V.
In the prior art described above, the voltage produced from the socket is a commercial AC voltage, and therefore, if the load needs the power of a different specification, it is necessary to insert power conversion means in the load or between the socket and the load.